Since nopCommerce Version 3.60 the payment methods are not included in DefaultClean and from that moment on we have stopped to include them in all the themes that we develop. For some themes, like Emporium, for example, you will see that such information is present. If you want to add them you will have to add the markup to the \Themes\Minimal\Views\Shared\Components\Footer\Default.cshtml file and the styling either in the styles.css file or in the Custom Head Styles textfield in the administration. If you like you can submit us a ticket via our Ticketing system and we can give you more info there.